Private Pilot License (PPL) Aerodynamics Practice Exam

Which arc on an airspeed indicator indicates safe stall speeds with flaps extended?

1. Green

2. Amber

3. White

4. Red

The correct answer is: White

The white arc on an airspeed indicator represents safe stall speeds with flaps extended. This portion of the indicator is critical for pilots as it signifies the range of airspeeds at which the aircraft can safely be flown with the flaps down. Typically, the lower limit of this arc indicates the stall speed in the landing configuration, while the upper limit indicates the maximum airspeed for flap extended operations. Understanding this range is particularly important during approaches, landings, and takeoffs, where the use of flaps is common to enhance lift and reduce landing speed. By operating within the confines of the white arc, a pilot ensures that they are well above stall speed while benefitting from the increased lift that flaps provide. This knowledge is fundamental for maintaining safety and effectiveness during flight maneuvers involving flap deployment.